Tapered Pipe System and Method for Foundation Support

ABSTRACT

A piling structure is provided. The piling structure includes a first piling section and a second piling section. At least one of the first and second piling sections has a tapered portion. An end of one of the first and second piling structures fits inside an end of the other of the first and second piling sections to form an overlap region where the first and second piling sections are coupled. In operation, the first piling section may be driven partially into strata. The second piling section may be coupled to the first piling section, and the combined piling structure may be driven further into the strata. The piling structure may be used to support a raised foundation structure.

TECHNICAL FIELD

The disclosure relates generally to foundation construction and repair and, more particularly, to a system and method for driving foundation pilings with tapered ends in connection with an apparatus that is adapted to raise and support foundation structures.

BACKGROUND

Buildings, including houses, office buildings, strip malls and the like, are often constructed such that a building frame, or other structural component, rests on a foundation. Foundation types are generally known and can include concrete slabs, reinforced concrete slabs, pier-and-beam, footings, and other types. Sometimes foundations include structures that are deep enough to contact, or tie into, solid strata such as bedrock. Other foundations are made shallow and rest on soil above the bedrock. These foundations may include structures, such as concrete slabs for example, that distribute the weight of the building across a relatively large area of the soil.

Changing soil conditions and/or improper building construction can result in portions of the building sagging or drooping. This can be caused by parts of the foundation sinking where the soil conditions are insufficient to support the structure. The sagging and drooping can, in turn, cause damage to the frame, drywall, flooring, plumbing, and other components of the building.

When a foundation structure such as a slab sinks, it becomes necessary to raise the sinking portion and support it such that it does not re-settle or sink further. Prior techniques have involved jacking up the slab and positioning pilings below the foundation for support. However, the pilings are not in contact with the solid strata, so additional foundation sinking can still occur. Additionally, these techniques can be very expensive and can be visually unpleasing as the repair components such as the pilings are typically visible after the repair work is completed.

Some prior systems involve driving a series of pipes or other foundation support structures into the ground. The pipes may be driven hydraulically or with a helix-type drive. A first pipe section is driven to a desired depth. Assuming that a ground, or downward, end of the pipe has not yet reached bedrock or some other stable strata, it is necessary to affix a second pipe section to the upward end of the first pipe section and then continue the pipe driving process. Prior systems have employed a coupling section to join the two foundation support pipe sections. The coupling section has an inner diameter slightly larger than the outer diameter of the joining ends of the two foundation support pipe sections. The coupling section overlaps the abutting joint between the two foundation support pipe sections and is affixed to the pipe sections (e.g., by weld or bolts) to join the two foundation support pipe sections.

SUMMARY

With prior foundation support driving methods utilizing pipe sections, two respective pipe ends had to be joined using a coupling section. In these prior systems, the coupling section has an inner diameter slightly larger than the outer diameter of the joining ends of the two foundation support pipe sections. The coupling section overlaps the abutting joint between the two foundation support pipe sections and is affixed to the pipe sections (e.g., by weld or bolts) to join the two foundation support pipe sections.

It has been discovered that these prior systems are deficient for a number of reasons. First, the need for a coupling section to join two foundation support pipe sections results in additional materials and a higher cost of the system. Second, adding a coupling section makes the system more complex and, therefore, more difficult to use and install. This can result in lengthening the necessary time for foundation repair work. Third, because the two joined pipe ends have the same diameter, the pipe ends are resting on one another when driven into the ground. This does not provide particularly good stability in the overall foundation support. Although the coupling section receives some of the stress of the coupling, some of the stress can be imparted to the pipe ends.

In view of the deficiencies of prior foundation support systems, certain embodiments of the invention provide an apparatus for use in foundation support systems and methods. The apparatus may include a foundation support structure, such as a piling, which may have a plurality of sections. The sections may be pipes or any other suitable structures which may be used in the foundation support system.

A piling may have a first, lower or ground end, which may include a helix tip. The helix tip may include a plurality of helix blades that are designed to drill into the ground and pull the first piling section downward. A second, or upper, end of the first piling section has a tapered portion such that a first, or lower, end of a second piling section may be fitted onto the upper end of the first piling section, thereby creating an overlap region of the two combined piling sections. The two piling sections may be affixed to one another (e.g., by a weld, one or more bolts, or other suitable connections).

According to one example embodiment an apparatus for supporting at least a portion of a building structure is provided. The apparatus includes a piling, which has multiple piling sections. A first piling section is adapted to be coupled to a second piling section. At least one of the first and second piling sections has a first end and a second end. One of the first and second ends is adapted to be driven into strata upon which the building structure is disposed. The other of the first and second ends has a tapered portion adapted for coupling to an end of the other piling section.

In another embodiment a method is provided for driving a piling. One step of the method is driving a first end of a first piling section into strata until a predetermined length of the first piling section remains exposed above the strata. The first piling section has a second end. Another step of the method is coupling a first end of a second piling section to the exposed second end of the first piling section to form a piling structure. The first end of the second piling section has an inner diameter that is different than the inner diameter of the second end of the first piling section. At least one of the coupled ends of the first and second piling section is tapered so that at least one of the coupled ends fits inside the other of the coupled ends. Another step of the method is driving the piling structure deeper into the strata.

In another embodiment an apparatus is provided for forming a piling structure. The apparatus includes a body portion and a tapered portion extending from an end of the body portion. The body portion and the tapered portion form a first piling section. The tapered portion is adapted to couple to an end of a second piling section to create an overlap area wherein an end of one of the first and second piling sections fits inside an end of the other of the first and second piling sections to form a piling structure adapted to be driven into strata.

In another example embodiment, a piling structure is provided and includes a first piling section and a second piling section. At least one of the first and second piling sections has a tapered portion. An end of one of the first and second piling structures fits inside an end of the other of the first and second piling sections to form an overlap region where the first and second piling sections are coupled.

In another example embodiment a method for forming a piling is provided. A first piling section is driven partially into strata. A second piling section is coupled to the first piling section to form a piling structure, which may be driven further into the strata. To couple the first and second piling sections, one end of one of the first and second piling sections is fitted inside an end of the other of the first and second piling sections to form an overlap region. The piling structure may be used to support a raised foundation structure.

One or more of the embodiments may provide some, none, or all of certain of the following advantage. One advantage is that with the joining configuration of certain embodiments, no extra material is needed. This can result in less expensive and simpler foundation support systems, as well as shorter repair times.

The various embodiments may present other advantages, and may include various other features and aspects. These additional advantages, features, and aspects will be apparent to one of ordinary skill in the art from the drawings, the detailed description, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of this disclosure and its features, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a partial elevation of two pipe sections for a foundation support system in accordance with one example embodiment;

FIG. 2 is a partial elevation of the two pipe sections of FIG. 1, wherein the two pipe sections have been joined and affixed to one another in accordance with one example embodiment;

FIG. 3 is a partial elevation showing three pipe sections joined together and further illustrating a helix blade system on one end of a first pipe section driving the combined pipe sections into the ground in accordance with an example embodiment;

FIG. 4 is an elevation of a combined piling affixed to a building structure via a foundation support element in accordance with an example embodiment.

FIG. 5 is a side view of a pipe section having a tapered portion with an S-shaped profile in accordance with an example embodiment;

FIG. 6 is a side view of a pipe section having a tapered portion with a linear profile in accordance with an example embodiment;

FIG. 7 is a side view of a pipe section having a tapered portion with a stepped profile in accordance with an example embodiment; and

FIG. 8 is a side view of a pair of pipe sections welded together in accordance with an example embodiment.

DETAILED DESCRIPTION

Various embodiments are illustrated in FIGS. 1-4. In summary, the various embodiments provide a tapered pipe or piling system for use in foundation support systems and methods. The tapered piling system includes a first, or lead piling section having a first ground-penetrating, or lower, end and a second, or upper, end. The lead piling section may be driven into the ground toward stable strata such as bedrock. The term piling is not intended to be limited and refers to any foundation support structure which may be driven into earth or other material, and toward strata upon which a building structure rests. The piling is preferably a component which may be affixed to the building structure to raise or lower at least a portion thereof.

Similarly, the term building structure is also not intended to be limiting and may refer to any structure that is disposed upon or above strata. Thus, the term building structure may refer to buildings, homes, office buildings, apartments, town homes, warehouses, retail buildings, storage facilities, silos, power plants, chemical facilities, industrial structures, garages, walls, piers, docks, seawalls, retaining walls, foundations, footers, concrete slabs, bridges, railroads, and/or any other type of manmade structure that may rest upon, or above, the ground or other strata.

The driving mechanism may be a hydraulic system having a drive head. Alternatively, the driving mechanism may be a helix system in which the lead piling section has a helix tip with helical blades. With this system, the piling is rotated such that the helix blades screw into the ground. While certain embodiments are described in connection with these driving mechanisms, they are examples only, and any driving mechanism may be employed. Thus, the described embodiments have applicability whenever the system utilizes multiple piling sections.

If the first piling section is driven to a maximum distance, such that the upward end is at its lowest useful point, and the lower end has not reached bedrock, a second piling section may be affixed to the first piling section. A first, or lower, end of the second section is affixed to the second, or upward, end of the first piling section. The combined piling may then be driven further into the ground. This may be repeated, with piling sections being added, until the first piling section contacts stable strata, such as bedrock, thereby meeting a predetermined amount of resistance. It should be understood that certain embodiments have usefulness in configurations where the overall piling structure is not driven into contact with bedrock. And, in these situations, a predetermined resistance causing cessation of the driving process may be less than that associated with reaching bedrock.

The upward end of each piling section may be tapered so that there is a portion of the upward end having an outer diameter that is slightly less than an inner diameter of the corresponding lower end of the piling section being connected. In this way the upward end of a given piling section is inserted into the lower end of the adjacent piling section. An overlap region is created and extends along the length of the portion of the reduced-diameter upward end of the respective piling section. The two piling sections may be affixed to one another (e.g., by weld, bolts, or other connections) in the area of the overlap region.

Certain embodiments are described in terms of one or more pipe ends being tapered and with an upper end of a lower pipe section being tapered to fit inside the lower end of an upper pipe sections. However, it should be understood that the tapered-end pipe sections may be joined with other taper configurations. For instance, the sections may be joined in a reverse direction. That is, an upper end of a pipe section may have the same diameter as the body of that section, while the lower end of the pipe section above it has a tapered end. Thus the lower end of the upper pipe section fits into the upper end of the lower pipe section. In still another alternative embodiment, the lower end of an upper pipe section has a diameter that is expanded or widened so as to fit over the upper end of the lower pipe section. In this case, the upper end of the lower pipe section may have either a diameter which is the same as the diameter of its body, or a tapered diameter. This configuration may also be reversed so that the upper end of the lower pipe section has a widened diameter to receive a lower end of the upper pipe section. Other alternatives may exist so long as one or both joined ends of respective pipe sections are tapered or widened. In certain places in the description, the terms “tapered” and “widened” are used interchangeably.

FIG. 1 illustrates two adjacent piling sections that are not yet connected. Collectively, the piling sections form piling system 10. A first piling section 12 has a first end 13 and a second end 14. Second end 14 is tapered. In the illustrated embodiment, the taper begins at a predetermined point along the length of first piling section 12. This is shown as point 30 on the outer surface of first piling section 12. The taper begins along all surface points around first piling section 12, where the surface points define a circumference and are at the same distance as point 30 from either respective end of first piling section 12. The taper has a reverse-curve profile. The reverse-curve, or S-shaped, profile is illustrated, for example, in FIG. 5. Thus, the sidewall of first piling section 12 curves inwardly to an inflection point and then begins to curve in the opposite direction until the sidewall is again parallel with a longitudinal axis of the piling section. The beginning point of the taper is shown at point 30 on the sidewall of first piling section 12. The inflection point is shown as point 31. The ending point of the taper is shown as point 32.

First piling section 12 may be viewed as having a first-width, or first-diameter portion 15. Section 12 also has a second-width, or second-diameter portion 17. Portion has a smaller, or reduced diameter as compared with portion 15. The first and second portions 15 and 17 both have a sidewall that is relatively parallel with the longitudinal axis of the piling section. First and second portions 15 and 17 are joined by transition portion 16. Transition portion 16 reduces the width, or outside diameter, of the first piling section 12. First piling section 12 may be viewed as having a tapered end portion 11 that extends from the beginning taper point 30 to the second end 14 of first piling section 12.

FIG. 1 also shows a second piling section 22. Preferably, second section 22 is substantially identical to first piling section 12. Thus, second piling section 22 has a first end 23 and a second end 24. Second end 24 is tapered beginning at a perimeter about the piling section that is defined by point 40. The taper has a reverse-curve profile. Thus, the sidewall of second piling section 22 curves inwardly to an inflection point and then begins to curve in the opposite direction until the sidewall is again parallel with a longitudinal axis of the piling section. The beginning point of the taper is shown at point 40 on the sidewall of first piling section 12. The inflection point is shown as point 41. The ending point of the taper is shown as point 42.

Second piling section 22 may be viewed as having a first-width, or first-diameter portion 25. Section 22 also has a second-width, or second-diameter portion 27. Portion has a smaller, or reduced diameter as compared with portion 25. The first and second portions 25 and 27 both have a sidewall that is relatively parallel with the longitudinal axis of the piling section. First and second portions 25 and 27 are joined by transition portion 26. Transition portion 26 reduces the width, or outside diameter, of the second piling section 22. Second piling section 22 may be viewed as having a tapered end portion 21 that extends from the perimeter at the beginning taper point 40 to the second end 24 of first piling section 22.

Second end 14 of first piling section 12 has an outer diameter that is slightly smaller than an inner diameter of the first end 23 of second piling section 22. Thus, second end 14 of first piling section 12 fits inside of first end 23 of second piling section 22. In this manner, second piling section 22 may be positioned onto the second end of first piling section 12. Second piling section 22 can slide down on first piling section 12 until it reaches a point in the taper portion 16 where the outer diameter of first piling section 12 is the same as the inner diameter of first end 23 of second piling section 22. At this point, second piling section 22 may move no further downwardly along first piling section 12. This stopping point is either at or slightly below the ending point 32 of the taper of first piling section 12.

The joining of first and second piling sections 12 and 22 creates an overlap region, which extends longitudinally along the combined piling sections from a point coinciding with second end 14 of first piling section 12 downward to a point coinciding with first end 23 of second piling section 22. This overlap section, among other things, provides stability to the combined piling sections. The length of the overlap section may be adjusted, for example, by increasing or decreasing the distance between second end 14 of first piling section 12 and ending point 32 of taper section 16. A longer overlap section may provide a more stable connection between the piling sections.

It should be noted that the described configuration of the taper sections is an example only. Some alternative configurations have already been described. Other configurations exist as will be apparent. For instance, the taper may begin at a certain point and have a straight-line profile ending at a second point inward toward the piling's longitudinal axis from the first point. The straight-line, or linear, profile is illustrated, for example, in FIG. 6. With a linear profile, it should be noted that there is no inflection point. In another example, the tapered end may be configured in more of a step-like manner in which the outer wall of the first piling section angles inward at roughly ninety degrees from the surface of first portion 15 and then turns ninety degrees again to continue parallel to the piling's longitudinal axis. The stepped profile is illustrated, for example, in FIG. 7. This latter configuration, for example, creates an annular step, or ledge, which the outer wall of the second piling section rests on when the second piling section is fitted onto the first piling section. The tapered end may have any other suitable configuration and/or profile. In other embodiments, for example, the tapered portion may have a shape that is conical, bulbous, stepped cylindrical, stepped hollow box, etc. with the inner and/or outer dimensions (perpendicular to the longitudinal axis of the piling section) increasing or decreasing toward the tapered end of the piling section.

It should also be understood that the combined piling may include more than two piling sections. Multiple piling sections may be repeatedly fitted onto one another as the combined piling is driven or screwed into the ground until the lower-most end of the first piling section comes into contact with stable strata such as bedrock.

As shown in FIG. 2, once two piling sections are fitted together, they may be affixed to one another. Any suitable joining technique may be used. The illustrated embodiment includes a pair of bolts 45 inserted through holes 46 in the overlap region of the first and second piling sections 12 and 22. An alternative method of affixing first and second piling sections 12 and 22 to one another might consist of a weld. The weld can be made, for example, completely or partially around the contact point between first end 23 of second piling section 22 and the outer surface of first piling section 12. A welded connection is illustrated, for example, in FIG. 8, where a weld 47 affixes piling section 12 to piling section 22. Affixing first and second piling sections 12 and 22 to one another lends additional stability to the combined piling and prevents the piling sections from coming apart if the piling is moved in certain directions.

Moreover, and particularly with respect to pilings that are helically driven, the connection between the piling sections allows the entire combined piling to be rotated without one piling section slipping or remaining stationary with respect to one or more other piling sections. For instance, if the uppermost piling section was being rotated, and if it was not affixed to the next lower piling section, the uppermost piling section might spin while the adjacent piling section already in the ground remained stationary due to the friction between its outer surface and the ground.

FIG. 3 illustrates a combined piling having first, second, and third piling sections 12, 22 and 52. First piling section 12 has a series of helix blades 60 disposed on a first, or lower, end thereof. Helix blades 60 may be separately formed and attached to the piling section or may be formed as part of the piling section. Helix blades 60 help drive or screw the piling section into the ground.

As mentioned previously, and as an alternative, the piling may be driven into the ground by a known hydraulic drive system. The drive system may have one or more ram units with corresponding pistons and arms driven by the pistons. Accordingly, the one or more ram units may be actuated simultaneously to cause a retracting motion of their corresponding pistons and arms, causing a clamp assembly to grab or clamp the piling and force it downward as needed. Other driving mechanisms and methods may be used as desired.

In practice, and according to another example embodiment, the first piling section is driven into the ground. At a certain distance, the lower end of the first piling section has not yet encountered bedrock or otherwise stable strata. However, the first piling section has been driven to a depth in which there is still a workable upper end. The second piling section is positioned onto the first piling section and affixed thereto. The driving process is continued driving the combined piling further into the ground. While there is still a workable upper end of the second piling, but before the piling has reached stable strata, the third piling section is positioned onto the second piling section and affixed thereto. Then the driving process is continued. Adding piling sections and repeating the driving process is continued until the lower end portion of the combined piling encounters a predetermined resistance in the ground, which is usually in the form of bedrock or otherwise stable strata, in which case the aforementioned driving process is terminated.

As illustrated in FIG. 4, after the piling has been driven to bedrock, a lifting plate 72 coupled to the piling 10 may be activated. Lifting plate 72 may be positioned below a structural element 70 of a building. For example, the lifting plate 72 may be positioned under the edge of a concrete slab foundation that has settled. A hydraulic system, or other type of system (not expressly shown), may be actuated to raise lifting plate 72, and therefore the building foundation 70 upward along the piling. When the foundation element is raised to the desired height, the lifting plate 72 may be affixed to the piling to provide permanent support.

Although the present invention has been described with several embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention encompass such changes and modifications as falling within the scope of the appended claims. 

1. An apparatus for supporting at least a portion of a building structure, the apparatus comprising: a piling, the piling comprising a plurality of piling sections, the plurality of piling sections comprising a first piling section and a second piling section adapted to be coupled to the first piling section, the first piling section having a first end and a second end, the first end being adapted to be driven into strata upon which the building structure is disposed, the second end having a tapered portion adapted for coupling to an end of the second piling section the first and second piling sections being connected to one another to enable rotational energy to be transmitted between the first and second piling sections.
 2. The apparatus of claim 1, wherein the first piling section has a first end adapted to be driven into the strata and a second end having a tapered portion adapted to fit inside a first end of the second piling section.
 3. The apparatus of claim 1, wherein the first piling section has a first end adapted to be driven into the strata and a second end having a tapered portion, and wherein a first end of the second piling section is adapted to fit inside the tapered portion of the second end of the first piling section.
 4. The apparatus of claim 1, wherein the first piling section has a first end adapted to be driven into the strata and a second end, and wherein the second piling section has a first end having a tapered portion adapted to fit inside the second end of the first piling section.
 5. The apparatus of claim 1, wherein the first piling section has a first end adapted to be driven into the strata and a second end, and wherein the second piling section has a first end having a tapered portion, the second end of the first piling section adapted to fit inside the tapered portion of the first end of the second piling section.
 6. The apparatus of claim 1, wherein the tapered portion tapers from a first dimension at the other of the first and second ends to a second dimension, and wherein the first dimension is less than the second dimension.
 7. The apparatus of claim 1, wherein the tapered portion is tapered from a first dimension at the other of the first and second ends to a second dimension, and wherein the first dimension is greater than the second dimension.
 8. The apparatus of claim 1, wherein the tapered portion has an S-shaped profile.
 9. The apparatus of claim 1, wherein the tapered portion has a linear profile.
 10. The apparatus of claim 1, wherein the tapered portion has a stepped profile.
 11. The apparatus of claim 1, wherein the first piling section is cylindrical, wherein the first piling section further comprises a body portion, the tapered portion extending from an end of the body portion to the other of the first and second ends.
 12. The apparatus of claim 11, wherein the tapered portion has a first inner diameter at the other of the first and second ends and a second inner diameter where the tapered portion meets the body portion, and wherein the first and second inner diameters are different.
 13. The apparatus of claim 12, wherein the first inner diameter is less than the second inner diameter and wherein the other of the first and second ends is adapted to fit inside the end of the other piling section.
 14. The apparatus of claim 12, wherein the first inner diameter is greater than the second inner diameter and wherein the other of the first and second ends is adapted to fit over the end of the other piling section.
 15. A method for driving a piling, comprising the steps of: driving a first end of a first piling section into strata until a predetermined length of the first piling section remains exposed above the strata, the first piling section having a second end; coupling a first end of a second piling section to the exposed second end of the first piling section to form a piling structure, the first end of the second piling section having an inner diameter that is different than an inner diameter of the second end of the first piling section, and at least one of the coupled ends of the first and second piling sections being tapered so that at least one of the coupled ends fits inside the other of the coupled ends; and rotating the second piling section to transmit rotational energy to the first piling section to drive the piling structure deeper into the strata.
 16. The method of claim 15, wherein the second end of the first piling section is tapered to fit inside the first end of the second piling section.
 17. The method of claim 15, wherein the second end of the first piling section is tapered to fit over the first end of the second piling section.
 18. The method of claim 15, wherein the first end of the second piling section is tapered to fit inside the second end of the first piling section.
 19. The method of claim 15, wherein the first end of the second piling section is tapered to fit over the second end of the first piling section.
 20. The method of claim 15, further comprising the step of affixing the coupled piling sections to one another.
 21. The method of claim 20, wherein the coupled ends of the first and second piling sections form an overlap region and wherein the affixing step further comprises inserting at least one bolt through at least one first hole in a sidewall of the first piling section and at least one second hole in a sidewall of the second piling section, the at least one first and second holes being aligned and being formed in the overlap region.
 22. The method of claim 20, wherein the affixing step comprises welding an inner edge of one end of the first and second piling sections to an outer surface of the other of the first and second piling sections.
 23. An apparatus for forming a piling, the apparatus comprising: a first piling section having a body portion; and a second piling section, the body portion of the first piling section having a tapered portion extending from an end of the body portion, the tapered portion adapted to couple to an end of the second piling section to create an overlap area wherein an end of one of the first and second piling sections fits inside an end of the other of the first and second piling sections to form a piling structure adapted to be driven into strata, the first and second piling sections being connected to one another to enable rotational energy to be transmitted between the first and second piling sections. 